Dispensing pump with polymer spring, base venting and flow baffle

ABSTRACT

A dispensing pump includes a polymer compression spring assembly, base vents and a flow baffle. The dispensing pump includes a pump base, and a dispensing head having a piston stem. The polymer compression spring assembly includes a slotted tubular spring element and first and second loading cones received at opposing ends of the slotted tubular spring element. The venting ports allow air to escape when capping the container after filling and the flow baffle reduces or prevents the product from being pulled into the pump accumulator before residual air (headspace) has been evacuated from the container during the initial priming strokes.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. application Ser. No.16/544,847, filed Aug. 19, 2019, which is continuation-in-part of U.S.application Ser. No. 16/163,685, filed Oct. 18, 2018 which is acontinuation of U.S. application Ser. No. 15/861,108, filed Jan. 3, 2018and issued as U.S. Pat. No. 10,138,971 on Nov. 27, 2018.

BACKGROUND OF THE DISCLOSURE

(1) Field of the Invention: The present invention generally relates todispensing pumps for liquids, viscous flowable materials, foams, gels,etc. and more particularly to a dispensing pump with a polymercompression spring assembly.

(2) Description of Related Art: Dispensing pumps for various liquids,lotions, foams, gels, etc. are known in the art. They generally comprisea body portion which is seated on the neck of a container, a co-actingnozzle portion which slides relative to the body portion, and a springstructure which biases the co-acting nozzle portion to its normal restposition. To dispense the material in the container, the user manuallydepresses the nozzle which forces the material from the inside of thebody portion outwardly through the nozzle. When the nozzle is released,the spring forces the nozzle portion back to its normal restingposition. Most of the pump system components are typically formed frompolymer materials, with the exception of the spring, which is typicallyformed from metal. The plastic pump components are easily recyclable.However, the presence of the metal spring in the pump assemblies hasbeen found to impede or slow the recycling process due to the need toseparate the metal spring from the other plastic components.Accordingly, there is a need in the industry for dispensing pump systemsincluding all plastic spring assemblies.

SUMMARY OF THE INVENTION

Exemplary embodiments of a dispensing pump for liquids, viscousmaterials, foams, gels, etc. include a polymer compression springassembly allowing the pump to be more easily recycled. The dispensingpump includes a pump base, and a dispensing head having an associatedpiston stem. The polymer compression spring assembly includes a slottedtubular spring element formed from a tensile polymer material and firstand second loading cones received at opposing first and second ends ofthe slotted tubular spring element. The piston stem extends coaxiallythrough the first loading cone, which is fixed on or in the pump base,and the second loading cone, which is axially movable with the pistonstem and dispensing head. The tubular spring element is disposedcoaxially about the piston stem between the first and second loadingcones. When the dispensing head is compressed, the loading cones areaxially compressible toward each other within the slotted tubular springelement whereby the slotted tubular spring element radially expands intension to create an opposing radial contraction force, and in turn, anaxial extension spring force. When released, the spring elementelastically returns to its normal at rest shape, returning the loadingcones and dispensing head to their normal at rest positions.

An exemplary embodiment of a compression spring assembly according tothe present invention includes a slotted tubular spring element formedfrom a tensile polymer material, and first and second loading conesreceived at opposing first and second ends of the slotted tubular springelement. In some embodiments, both the spring element and the loadingcones may be formed from polymer materials, making the spring assemblymore easily recyclable.

In an exemplary embodiment, the slotted tubular spring element iscylindrical in shape and has a uniform wall thickness. The loading conesare generally conical in shape and preferably have at least one wallsection with a wall angle of no less than 11 degrees. Wall angles ofless than 11 degrees tend to create a friction lock while wall angles ofgreater than 11 degrees minimize stroke length and increase overallspring assembly diameter. The exemplary embodiment includes loadingcones with a first frustoconical preloading wall section having a wallangle of greater than 11 degrees, and a second frustoconical primaryloading wall section having a wall angle of 11 degrees.

The loading cones are axially compressible toward each other within theopen ends of the slotted tubular spring element whereby the slottedtubular spring element radially expands in tension to create an opposingradial contraction force. Deformation of the tubular spring wallselastically stores energy which will return the spring to its normal atrest shape when released. When released, the spring element elasticallycontracts, in turn creating an axial extension force, and returns thecones to their normal at rest positions.

Some embodiments of the spring assembly include a modified springelement having strain reducing ribs extending along the opposing edgesof the longitudinal slot. The ribs may include outwardly convex surfacesextending both radially outward and circumferentially outward from theslot edges. This embodiment further includes a first thinner wallthickness at the slot edges and a second thicker wall thicknessdiametrically opposed from the slot edges. The arcuate surface alongwith the increasing wall thickness moving away from the slot edges, moreevenly distributes strain throughout the spring element and extends thelife cycle of the spring element.

Other embodiments of the spring assembly may include a spring elementwhich is hyperboloid in shape.

Still further embodiments of the spring element have thicker wallsections in select locations and strengthening ribs extendingcircumferentially around the spring and/or extending longitudinallyalong the height of the spring opposite the slot.

Some exemplary embodiments of the dispensing pump may include a pumpbase with venting ports around the peripheral sealing wall to allow airto escape when capping the container after filling.

Some exemplary embodiments of the dispensing pump may include a flowbaffle disposed over the inlet port of the pump base to reduce orprevent the product from being pulled into the pump accumulator beforeresidual air has (headspace) has been evacuated from the containerduring the initial priming strokes.

In some exemplary embodiments, all of the components of both thedispensing pump and the compression spring assembly are molded from thesame plastic material making the entire dispensing pump easilyrecyclable in a single plastic material classification. Exemplaryplastic materials include polypropylene (PP), high-density polyethylene(HDPE), and low-density polyethylene (LDPE). However, the disclosureshould not be considered to be limited to these materials.

BRIEF DESCRIPTION OF THE DRAWINGS

While the specification concludes with claims particularly pointing outand distinctly claiming particular embodiments of the instant invention,various embodiments of the invention can be more readily understood andappreciated from the following descriptions of various embodiments ofthe invention when read in conjunction with the accompanying drawings inwhich:

FIG. 1 is a plan view of an exemplary compression spring assembly inaccordance with the present invention;

FIG. 2 is a perspective view of the slotted tubular spring element in anat rest condition;

FIG. 3 is a perspective view of the slotted tubular spring element in aradially expanded condition;

FIG. 4 is a top view of the spring element;

FIG. 5 is a front view thereof;

FIG. 6 is a side view thereof;

FIG. 7 is a cross-section view thereof taken along line 7-7 of FIG. 4;

FIG. 8 is an enlarged plan view of the loading cone;

FIGS. 9-12 are sequential views of the compression spring assembly beingaxially loaded and released;

FIG. 13 is a cross-sectional view of an exemplary dispensing pumpincorporating the present compression spring assembly;

FIG. 14 is a front view of another exemplary embodiment of the slottedtubular spring element including strain reducing ribs;

FIG. 15 is a top view thereof;

FIG. 16 is a side view thereof;

FIG. 17 is a perspective view thereof in a radially expanded condition;

FIGS. 18 and 19 are side and front views thereof showing the bendingvectors of the ribs when the spring element is expanded;

FIG. 20 is an illustration showing initial axial compression of thespring assembly;

FIG. 21 is another illustration showing full axial compression of thespring assembly;

FIG. 22 is a plan view of another exemplary compression spring assemblyincluding a hyperboloid spring element;

FIG. 23 is a perspective view of the hyperboloid slotted spring element;

FIG. 24 is a front view thereof;

FIG. 25 is a top view thereof;

FIG. 26 is a cross-sectional view thereof taken along line 26-26 of FIG.25; and

FIG. 27 is a perspective view of an exemplary dispensing pumpincorporating a hyperboloid compression spring assembly;

FIG. 28 is a cross-sectional view thereof taken along line 28-28 of FIG.27;

FIG. 29 is a perspective view of another exemplary embodiment;

FIG. 30 is a cross-sectional view thereof taken along line 30-30 of FIG.29;

FIGS. 31-34 are cross-sectional views of additional exemplaryembodiments;

FIG. 35 is a perspective view of a preferred exemplary embodiment;

FIG. 36 is a front view thereof;

FIG. 37 is an exploded perspective view thereof;

FIG. 38 is a cross-sectional view thereof taken along line 38-38 of FIG.36;

FIG. 39 is a plan view of the accumulator;

FIG. 40 is a cross-sectional view thereof taken along line 40-40 of FIG.39;

FIG. 41 is a plan view of the second loading cone;

FIG. 42 is a cross-sectional view thereof taken along line 42-42 of FIG.41; and

FIGS. 43-48 are cross-sectional views thereof showing a complete pumpstroke sequence;

FIG. 49 is a perspective view of another exemplary embodiment;

FIG. 50 is an exploded perspective view thereof;

FIG. 51 is a cross-section view thereof;

FIGS. 52 and 53 are perspective view of the compression spring assembly;

FIGS. 54-58 are various view of the spring element;

FIGS. 59-64 are cross-sectional views thereof showing a completeactuation cycle and motion of the dispenser head and spring;

FIG. 65 is a perspective view of still another exemplary embodimentincluding a flow baffle and base vents;

FIG. 66 is an exploded perspective view thereof;

FIGS. 67-69 are various views of the cap base;

FIGS. 70 and 71 are various views of the flow baffle;

FIG. 72 is a bottom view of the dispensing head with the flow baffleassembled;

FIG. 73 is a cross-sectional view of the dispensing head taken alongline 73-73 of FIG. 65

FIG. 74 is another cross-section view thereof also showing the containerand piston follower;

FIG. 75 is a perspective view of yet another exemplary embodiment;

FIG. 76 is an exploded perspective view thereof;

FIGS. 77-78 are various views of the flow baffle;

FIG. 79 is a bottom view of the dispensing head with the flow baffleassembled;

FIG. 80 is a cross-sectional view of the dispensing head taken alongline 80-80 of FIG. 75;

FIG. 81 is a perspective view of a further exemplary embodiment;

FIG. 82 is an exploded perspective view thereof;

FIGS. 83-84 are various views of the flow baffle;

FIG. 85 is a bottom view of the dispensing head with the flow baffleassembled;

FIG. 86 is a cross-sectional view of the dispensing head taken alongline 86-86 of FIG. 81;

FIG. 87 is a perspective view of another exemplary embodiment includingbase vents and an alternative inlet port and flat valve;

FIG. 88 is an exploded perspective view thereof;

FIGS. 89-91 are various views of the pump base and disc valve; and

FIG. 92 is a cross-sectional view of the pump base taken along line92-92 of FIG. 87.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the drawings, an exemplary embodiment of the presentcompression spring assembly is generally indicated at 10 in FIG. 1-12.According to the present invention, the compression spring assembly 10comprises a slotted tubular spring element 12 formed from a tensilepolymer material, and first and second loading cones 14, 16 received atopposing first and second ends of the slotted tubular spring element 12.In some embodiments, the loading cones 14, 16 may be formed fromnon-plastic materials, depending on the implementation. However, in thepreferred embodiments as disclosed herein, both the spring element 12and the loading cones 14, 16 are formed from polymer materials.Exemplary plastic materials include polypropylene (PP), high-densitypolyethylene (HDPE), and low-density polyethylene (LDPE). However, thedisclosure should not be considered to be limited to these materials. Inparticular, the various components may be molded from HDPE and/or LDPE,making the entire spring assembly more easily recyclable.

In the exemplary embodiment, the slotted tubular spring element 12 iscylindrical in shape and has a uniform wall thickness (best illustratedin FIGS. 2 and 4). The spring element 12 includes a single longitudinalslot 18 which extends the entire length of the tube to define parallelopposing slot edges 20, 22. The slot 18 allows the element 12 to expandradially upon the application of an axial force at the first and secondends thereof. The inner wall edges are chamfered 24 to facilitatesliding of the walls over the loading cone surfaces 14. 16 (bestillustrated in FIG. 7).

The loading cones 14, 16 are identical in shape and are symmetricallyinverted to provide opposing axial compression and extension forces onthe tubular spring element 12. Referring to FIG. 8, the loading cones14, 16 (only 14 is shown) are generally conical in shape and preferablyhave at least one wall section (primary loading wall) 26 with a wallangle θ¹ of no less than 11 degrees. In the present embodiment, a wallangle of less than 11 degrees tends to create a friction lock while awall angle of greater than 11 degrees minimizes stroke length andincreases overall spring assembly diameter. It should be understood thatthe critical wall angle for the primary loading wall 26 is based on thetype of material used, i.e. polymer or metal, and other factors such assurface finish, shape of wall chamfers, etc. The angle must be selectedsuch that the spring force from the spring element 12 overcomes frictionas well as displacement of the applied axial load. The exemplaryembodiment, which has an intended use in dispensing pumps for viscousliquids, includes loading cones 14, 16 with a first frustoconicalpre-loading wall section 28 having a wall angle θ² of greater than 11degrees, and a second frustoconical primary loading wall section 26having a wall angle θ¹ of 11 degrees. The steeper pre-load angle θ²facilitates the initial expansion of the spring element 12.

Turning to FIGS. 9-12, the loading cones 14, 16 are axially compressibletoward each other within the open ends of the slotted tubular springelement 12 whereby the slotted tubular spring element 12 radiallyexpands in tension to create an opposing radial contraction force. FIG.9 illustrates an initial at rest state. FIG. 10 illustrates initialpre-load and outward expansion of the spring element. FIG. 11illustrates full axial compression and load. Deformation of the tubularspring element 12 elastically stores energy which will return the springelement 12 to its normal at rest shape when released. When released asillustrated in FIG. 12, the spring element 12 elastically contracts(inward), in turn creating an axial extension force, and returns thecones 14, 16 to their normal at rest positions.

Turning to FIG. 13, embodiments of the present polymer compressionspring 10 may be advantageously used in a dispensing pump 100 forvarious liquids, lotions, etc. contained within a bottle or othercontainer (not illustrated). In some exemplary embodiments, all of thecomponents of both the dispenser pump 100 and the compression springassembly 10 are molded from the same plastic material making the entiredispensing pump 100 including the spring assembly 10 easily recyclablein a single plastic material classification.

The dispensing pump 100 comprises an accumulator cup 102 having a cliptube receptacle 104 and ball valve 106 at a lower end thereof. A tubularguide 108 is received in the upper end of the accumulator cup 102, andthe tubular guide 108 is secured on a container neck (not shown) with athreaded cap ring 110. The present compression spring assembly 10 isreceived and guided within the tubular guide 108. As noted above, theangle θ¹ of the loading wall 26 of the loading cones 14, 16 is acritical factor in determining overall spring assembly diameter. As seenin this pump embodiment 100, the spring assembly 10 fits within theinner walls of the guide 108 which in turn must fit within the neck ofthe container. Accordingly, the wall angle, spring element material andprofile are all factors in determining this specification. A piston rod112 is received axially through the loading cones 14, 16 and the tubularspring element 12 and extends through the bottom of the guide 108 intothe accumulator cup 102 wherein the terminal end is fitted with a piston112 which forms a seal with the inner wall of the accumulator 102. Anozzle head 116 is secured to the upper end of the piston rod 112 andreceived over the upper loading cone 16.

In operation, a forcible downward compression of the nozzle head 116causes a corresponding downward axial movement of the upper loading cone16 and outward deflection and loading of the spring element 12 as perthe illustrations earlier described in FIGS. 9-12. Upon the subsequentrelease of the nozzle head 116, the tubular spring element 12elastically contracts back to its normal at rest shape and position (seealso FIG. 12), causing a forcible upward movement of the upper loadingcone 16, piston rod 112, piston 114 and nozzle head 116 back to theirnormal at rest positions. The pump assembly 100 and ball valve 106operate as known in the art to draw material up from the dip tube 104and dispense the material through the nozzle head 116.

Turning now to FIGS. 14-21, some embodiments of the spring assembly 200may include a modified slotted tubular spring element 202 having strainreducing ribs 204, 206 extending along the opposing edges 208, 210 ofthe longitudinal slot 212. The ribs 204, 206 may include symmetricalconvex surfaces extending both radially outward 204 a, 206 a (See FIGS.15 and 16) and circumferentially outward 204 b, 206 b (See FIG. 14) fromthe slot edges 208, 210. This embodiment 202 further includes a firstthinner wall thickness 214 at the slot edges 208, 210 adjacent thestrain ribs 204, 206 and a second thicker wall thickness 216diametrically opposed from the slot edges 208, 201 (See FIG. 15). Thearcuate surfaces 204 a, 204 b, 206 a, 206 b along with the increasingwall thickness moving away from the slot edges 208, 210 more evenlydistributes strain throughout the entire spring element 202 and extendsthe life cycle of the spring element 202. FIG. 17 illustrates the springelement 202 in an expanded loaded state. FIGS. 18 and 19 illustrate themovement vectors (arrows) associated with the corners of the slot edges208, 210. The reduced material volume in these areas allow these cornersto more easily deform and reduce strain. The present spring element 202is used in combination with the same loading cones 14, 16 as previouslydescribed. FIGS. 20 and 21 show axial compression of the presentembodiment 200 with exemplary loading cones 14, 16. The present springassembly 200 can be used in the same types of dispensing pumps 100 asdescribed above with improved spring longevity.

Referring now to FIGS. 22-28, other embodiments of the compressionspring assembly 300 include a slotted tubular spring element 302 whichis hyperboloid in shape, i.e. having a smaller (narrower) diameter atthe center and symmetrically larger diameters at the ends, and first andsecond opposed loading cones 304, 306. The spring element 302 has auniform wall thickness (See FIGS. 25 and 26) and includes a singlelongitudinal slot 308 (FIGS. 23 and 24) which extends the entire lengthof the tube, allowing the spring element 302 to expand radially upon theapplication of an axial force at the first and second ends thereof. Thecurved spring wall of the hyperboloid spring 302 is provides a stifferloading profile (higher loading profile) using the same amount ofplastic material as compared with the earlier described cylindricalshape (FIGS. 1-12). The inner wall edges are also chamfered 310 tofacilitate sliding of the spring element 302 over the loading cone wallsurfaces 304, 306 (See FIG. 26). The hyperboloid shape of the springelement 302 works more efficiently with loading cones 304, 306 having asingle frustoconical loading wall 312 with a somewhat steeper wall angleθ³ (FIG. 22). The preferred embodiment as illustrated shows a wall angleθ³ of greater than 11 degrees. As noted above, the particular wall angleθ is selected based on the tensile characteristics of the spring element302 as well as material and surface finishes. The exemplary embodimentsare intended to be illustrative but not limiting.

Turning to FIGS. 27 and 28, the present hyperboloid compression springassembly 300 lends itself to be advantageously used as an exteriorspring return in certain dispensing pumps 400 for various liquids,lotions, etc. As described above, in many exemplary embodiments, all ofthe components of both the dispenser pump 400 and the compression springassembly 300 are molded from the same plastic material making the entiredispensing assembly easily recyclable in a single plastic materialclassification.

Referring to FIGS. 27-28, the dispensing pump 400 comprises anaccumulator cup 402 which is secured within the neck of a container 404with a threaded closure 406. A nozzle head 408 is received on a pistonstem 410 which extends through the closure 406 and into the accumulator402. A piston seal 411 is received on the terminal end of the pistonstem 410, forming a seal with the inner walls of the accumulator. Theloading cones 304, 306 of the present hyperboloid compression springassembly 300 are integrated into the opposing exterior surfaces of theclosure 406 and the top end of the piston stem 410 and the hyperboloidslotted tubular spring element 302 is snap received over and around thepiston stem 410 and upward cone extension 304 of the closure 406 so thatit engages the ramped loading cone walls 304, 306 of the piston stem 410and closure 406.

In operation, a forcible downward compression of the nozzle head 408causes a corresponding downward axial movement of the upper loading cone(piston stem head) 410/306 and outward deflection and loading of thespring element 302 similar to the illustrations earlier described inFIGS. 9-12. Upon the subsequent release of the nozzle head 408, thetubular spring element 302 elastically contracts (radially inward) backto its normal at rest shape and position, causing a forcible upwardmovement of the upper loading cone (piston stem) 410/306 and nozzle head408 back to their normal at rest positions. The pump assembly 400operates as known in the art to draw material up from a clip tubeconnection 412 and dispense the material through the nozzle head 408.

Referring to FIGS. 29 and 30, another exemplary pump dispenserembodiment is illustrated and generally indicated at 500. The dispensingpump 500 comprises an accumulator 502 which is secured within the neckof a container 504 with a threaded closure 506. The accumulator 502 hasa dip tube inlet 508 formed in the bottom wall thereof. A nozzle head510 is received on a piston stem 512 which extends through a secondclosure ring 514 secured at the top of the accumulator 502 and into theaccumulator 502. A piston seal 516 received on the terminal end of thepiston stem 512, forming a seal with the inner walls of the accumulator502. The compression spring assembly 518 is received within theaccumulator 502, similar to the embodiment in FIG. 13, and comprises acylindrical slotted tubular spring element 520 and first and secondloading cones 522, 524. The first loading cone 522 of the presentembodiment is an independent component which is seated on a shoulder 526formed on the accumulator wall. The piston stem 512 extends coaxiallythrough the first loading cone 522 such that the piston seal 516 islocated below the first loading cone 522. The second loading cone 524 isintegrated into the exterior surface of the piston stem 512. It is notedhere that the loading cones 522, 524 have a single uniform loadingsurface. The slotted tubular spring element 520 is received coaxiallyaround the piston stem 512 and between the first and second loadingcones 522, 524.

Operation of the dispensing pump 500 is similar to that described withrespect to the embodiment in FIG. 13.

Referring to FIG. 31, another exemplary embodiment is illustrated andgenerally indicated at 600. The dispensing pump 600 generally comprisesa pump base 602, a dispensing head 604 and a polymer compression springassembly 606. The pump base includes an accumulator 608 secured withinthe neck of a container (not shown) with a threaded closure 610. Theaccumulator 608 has a dip tube inlet 612 formed in the bottom wallthereof and a ball valve 614 is located within the dip tube inlet 612.The dispensing head 604 is received on the top end of a piston stem 616which extends through the threaded closure 610 and into the accumulator608. A piston seal 618 is received on the piston stem 616 midway alongthe length of the piston stem. The compression spring assembly 606 isreceived within the accumulator 608, and comprises a cylindrical slottedtubular spring element 620 and first and second loading cones 622, 624.The first loading cone 622 of the present embodiment is integrallyformed with the bottom wall of the accumulator 608 extending upwardlyaround the dip tube inlet 612 and ball valve 614. The second loadingcone 624 is integrated into the terminal end of the piston stem 616. Itis noted here that the piston stem 616 extends coaxially through thepiston seal 618 such that the piston seal 618 is located above thesecond loading cone 624. The loading cones 622, 624 have both apreloading surface and primary loading surface as described hereinaboveand better illustrated in FIG. 8. The cylindrical slotted tubular springelement 620 is received within the accumulator 608 between the first andsecond loading cones 622, 624.

Downward compression of the dispensing head 604 causes a correspondingdownward compression of the piston stem 616 and second loading cone 624,and elastic radial expansion of the slotted tubular spring element 620.Material within the accumulator chamber is pumped through a port 626 inthe wall of the piston stem 616 into an interior stem passageway andupwardly into the dispensing head 604. As described above, release ofthe dispensing head 604 frees the spring element 620 to radiallycontract and create an upward axial force to return the piston stem 616and dispensing head 604 back to their normal at rest positions.

FIG. 32 illustrates a slightly modified embodiment 600A where theinterior passage of the piston stem 616 is enlarged to improve materialflow.

FIG. 33 illustrates another modified embodiment 600B where the tip ofsecond loading cone 624 is truncated and the accumulator 608 is slightlyshorter in length.

FIG. 34 illustrates yet another embodiment 600C where the second loadingcone 624 is molded as a separate component and secured on a terminal endof the piston stem 616 below the piston seal 618.

Turning now to FIGS. 35-48, one exemplary embodiment of the dispensingpump is illustrated and generally indicated at 700. The dispensing pump700 comprises a pump base assembly 702, a dispensing head 704 and apolymer compression spring assembly 706. The pump base assembly 702includes an accumulator cup 708 that is secured within the neck of acontainer (not shown) with a closure ring 710. In the exemplaryillustration, the closure ring 710 is threaded for attachment to athreaded container neck. Referring to FIGS. 38 and 40, the accumulator708 has a dip tube inlet 712 formed in the bottom wall thereof and aball valve 714 is located within the dip tube inlet 712. The dispensinghead 704 is integrally formed at the top end of a piston stem 716 whichextends through the closure ring 710 and into the accumulator 708. Thepiston stem 716 is guided axially within the accumulator 708 by anannular chaplet 718 which is threadably received within the topperipheral edge of the accumulator 708. A piston seal 720 (see FIGS.37-38) is received on the piston stem 716 midway along the lengththereof.

The compression spring assembly 706 is received within the accumulator708, and comprises a cylindrical slotted tubular spring element 722 andfirst and second loading cones 724, 726. The first loading cone 724 ofthe present embodiment is integrally formed with the bottom wall of theaccumulator 708 and extends upwardly around the clip tube inlet 712 andball valve 714.

The second loading cone 726 is molded as a separate cup shaped componentwith an open top, a hollow interior and interior ribs 728 which are snapreceived onto corresponding ridges 730 the terminal end of the pistonstem 716. The ribs 728 are formed such that the terminal end of thepiston stem 716 is positioned slightly above the interior bottom wall ofthe loading cone 726 and such that a passage is provided from theinterior of the loading cone 726 into the interior passage 729 of thepiston stem 716 (see arrows in FIG. 38). It is noted here that thepiston stem 716 extends coaxially through the piston seal 720 such thatthe piston seal 720 is located above the second loading cone 726.Further the exterior surface of the second loading cone 726 includesradially outward guides 731 which assist proper sliding movement of theloading cone 726 within the interior wall of the accumulator 708.

The loading cones 724, 726 have both the preloading surface A andprimary loading surface B described hereinabove. The cylindrical slottedtubular spring element 722 is received within the accumulator 708between the first and second loading cones 724, 726. While the exemplaryembodiment herein is illustrated with a cylindrical tubular springelement 722 it should be understood that the spring element 722 maycomprise any of the herein described spring elements. Likewise, theloading cones 724, 726 may be formed with any of the configurationsdescribed herein above.

Turning to FIGS. 43-48 a complete dispensing sequence for the presentembodiment 700 is illustrated. FIG. 43 illustrates a starting positionwith the loading cones 724 slightly pre-loaded and the ball valve 714closing the dip tube inlet port 712. During assembly, the chaplet 718threads down into the top of the accumulator 708 and compresses thevarious components together in a slightly pre-loaded condition. Movingto FIG. 44, downward compression of the dispensing head 704 and pistonstem 716 causes a corresponding downward compression of the secondloading cone 726, the start of elastic radial expansion of the slottedtubular spring element 722, and opening of a dispensing passage betweenthe bottom of the piston seal 720 and the top edge of the second loadingcone 726. In FIG. 45, further downward compression of the dispensinghead 704 moves both the loading cone 726 and the piston seal 720providing pumping action. A set of circumferentially spaced guide ribs732 extending longitudinally down the exterior wall of the piston stem716 have terminal shoulders 734 which engage the center ring of thepiston seal 720 and cause corresponding downward movement thereof alongwith the dispensing head 704. Material within the accumulator 708 isforced down into the interior of the second loading cone 726, upwardinto the interior stem passageway 729 and upwardly into the dispensinghead 704. Turning to FIGS. 46-48, release of the dispensing head 704frees the spring element 722 to radially contract and create an upwardaxial force to return the piston stem 716, piston seal 720 anddispensing head 704 back to their normal at rest positions. In returningto the start position, the ball valve 714 is opened (FIG. 46) to drawfresh material from the container into the accumulator 708 (FIG. 47). Atcompletion of the pump stroke, the ball valve 714 re-seats itself toclose the dip tube inlet 712.

Turning now to FIGS. 49-64, another exemplary embodiment of a dispensingpump is illustrated and generally indicated at 800. The dispensing pump800 comprises a pump base 802, a dispensing head 804 and a polymercompression spring assembly 806. The pump base 802 includes an outerskirt wall 808 and an inner accumulator cup 810. A lower portion of theouter surface of the skirt wall 808 is snap received within the neck 812of a container or jar 814. In the exemplary illustration, the skirt wall808 and neck 812 include interfitting ridges for a snap fit attachmentto the container 814. A cup-shaped cap 816 is snap received over thedispensing head 804 onto ridges on an upper portion of the outer surfaceof the skirt wall 808.

The exemplary embodiment 800 as disclosed is an airless pump system andas such, includes a piston follower 818 received within the container814 which seals against the inner wall of the container 814.

Referring to FIGS. 51 and 59-64, the accumulator cup 810 has an inletport 820 formed in the bottom wall thereof and a ball valve 822 islocated within the inlet port 820.

The dispensing head 804 has an integrally formed outlet nozzle 824 withan outer shroud wall 826 and a downwardly extending inlet stem 828. Theouter shroud wall 826 has a lower peripheral edge portion which isreceived within the skirt wall 808 of the pump base 802. The peripheraledge portion includes a raised ridge 830 which interacts with acorresponding shoulder 832 extending inwardly at the upper peripheraledge of the skirt wall 808. The ridge 830 and shoulder 832 interact tomaintain the dispensing head 804 and pump base 802 in assembled relationand define an at-rest stop position (FIG. 59) of the pump assembly 800.

A piston stem 834 has an interior flow passage 836, an upper end 838which is assembled with the inlet stem 828 of the dispensing head 804and an opposed lower end 840 which extends downwardly into theaccumulator 810. The lower end 840 also has an inlet opening 842. Thepiston stem 834 is guided axially within the accumulator 810 by means ofan annular guide wall 844 which is concentrically received around theoutside of the accumulator 810. A piston seal 846 is received on thelower end 840 of the piston stem 834, sealing against the inner walls ofthe accumulator 810 and also sealing the inlet opening 842.

The compression spring assembly 806 is situated in the space between theouter skirt wall 808 and the outside of the accumulator 810 andcomprises a cylindrical slotted tubular spring element 848 and first andsecond loading cones 850, 852. The first loading cone 850 of the presentembodiment is integrally formed with the bottom wall of the pump base802 and extends upwardly concentrically around the outside of theaccumulator 810. The second loading cone 852 is disposed concentricallyaround the piston stem 834, and in the exemplary embodiment is molded asan integral portion of the guide wall 844 of the piston stem 834. Thesecond loading cone 852 moves with the dispensing head 804 and pistonstem 834 during the dispensing cycle. The loading cones 850, 852 mayhave both a preloading surface and primary loading surface describedhereinabove.

The spring element 848 is generally cylindrical in shape as above, andmay have strain reducing ribs 854, 856 extending along the opposingedges of the longitudinal slot 858. The spring element 848 may alsoinclude a strengthening/relief rib 860 extending circumferentiallyaround the outer wall of spring 844 and another spine rib 862 extendinglongitudinally along the height of the spring 848 opposite the slot 858.Referring to FIG. 58, the present embodiment includes a longitudinal rib862 that extends outwardly opposing the slot essentially forming alongitudinal spine of the spring. The circumferential rib(s) 860 extendcircumferentially around the spring element 848 from the longitudinalspine 862 toward the slot 858, gradually reducing in height untilmerging with the outer surface of the spring wall slightly more than 90degrees from the longitudinal back spine 862. Any, or all, of these ribs854, 856, 860, 862 may provide additional strength, resilience, strainrelief and spring force in shorter height spring elements.

While the exemplary embodiment herein is illustrated with a cylindricaltubular spring element 848 it should be understood that the springelement may comprise any of the herein described spring elements.Likewise, the loading cones 850, 852 may be formed with any of theconfigurations described herein above.

Turning to FIGS. 59-64, a complete dispensing sequence for the presentembodiment 800 is illustrated. FIG. 59 illustrates a starting positionwith the loading cones 850, 852 and spring 848 slightly pre-loaded, thepiston seal 846 captured against a bead 864 on the inside peripheraledge of the accumulator cup 810, the lower end 840 of the piston stem834 seated in the piston seal 846, and the ball valve 822 closing theinlet port 820. Moving to FIG. 60, downward compression of thedispensing head 804 and piston stem 834 causes downward compression ofthe second loading cone 852, the start of elastic radial expansion ofthe slotted tubular spring element 848, and opening of a dispensingpassage (842) in the bottom end 840 of the piston stem 834 which slidesrelative to the piston seal 846. Movement of the upper loading cone 852is stabilized by the guide walls 844 and further by an annular wall 865which extends downwardly from the dispensing head 804. The annular wall865 engages the outer periphery of the loading cone 852 to provide auniform downward compression. In FIG. 61, further downward compressionof the dispensing head 804 moves both the loading cone 852 and thepiston seal 846 providing pumping action. The ball valve 822 remainsseated in the valve seat within the inlet port 820. Material within theaccumulator 810 is forced into the interior passage 836 of the pistonstem 834, upward into the inlet stem 828 and upwardly into the nozzle824. Turning to FIGS. 62-64, release of the dispensing head 804 freesthe spring element 848 to radially contract and create an upward axialforce to return the piston stem 834, piston seal 846 and dispensing head804 back to their normal at rest positions (FIGS. 59 and 64). Inreturning to the start position, the piston inlet passage 842 is closedand the ball valve 822 is opened (FIG. 62) to draw fresh material fromthe container 814 into the accumulator 810 (FIG. 63) through the inletport 820. At completion of the return stroke, the ball valve 822re-seats itself to close the inlet port 820 (FIG. 64).

Turning now to FIGS. 65-74, another exemplary embodiment of a dispensingpump is illustrated and generally indicated at 900. The dispensing pump900 is substantially similar to the above-described embodiment 800 instructure and function with two exceptions. The pump 900 mayadditionally include venting structures 960 on the outer peripheralsurfaces of the pump base 902 as well as a baffle structure 970 which isdisposed over the inlet port 920 into the pump base 902, the purposes ofwhich will be described hereinbelow.

The major working components of dispensing pump 900 are essentially thesame. The dispensing pump 900 comprises a pump base 902, a dispensinghead 904 and a polymer compression spring assembly 906. The pump base902 includes an outer skirt wall 908 and an inner accumulator cup 910. Alower portion of the outer surface of the skirt wall 908 is snapreceived within the neck 912 of a container or jar 914. A cup-shaped cap916 is snap received over the dispensing head 904. The exemplaryembodiment 900 also further includes a piston follower 918. As similarlydescried above, the accumulator cup 910 has an inlet port 920 formed inthe bottom wall thereof and a ball valve 922 is located within the inletport 920.

A piston stem 934 and piston seal 946 are assembled with the dispensinghead 904 as also described above.

The compression spring assembly 906 is the same as described hereinabovecomprising a cylindrical slotted tubular spring element 948 and firstand second loading cones integrally formed with the pump base 902 andthe piston stem 934.

Turing to the present improvements, it has been found that in somecases, the inlet port 920 dips down into product within the container914 when the container 914 is first filled and capped. Withself-leveling products this is not an issue. However, withnon-self-leveling products, the pump 900 will start to produce an outputbefore air trapped in the headspace between the pump base and theproduct in the container has been evacuated. This issue causes variationin the output of each pump stroke. In this regard, the pump base 902 isprovided with a plurality of peripheral vents 960 or relief areas on theouter surface of the pump base skirt 908. During capping of the pumpbase 902 onto the container neck 912, the vents 960 allow air to escapeas the pump base 902 is seated down within neck 912. The vents 960prevent too much air from becoming trapped in the headspace when cappingand less air reduces the number of priming strokes before product isdispensed. The vents 960 may be grouped together (See FIG. 68) and mayalso be circumferentially spaced around the peripheral edge of the pumpbase 902 (See FIGS. 67-69). Additionally, the vents 960 may have tieredsizes from larger vents to smaller vents in the direction of air flowescaping the headspace (See FIG. 68).

The flow baffle 970 includes a central nipple portion 972 and a radiallyoutward extending flange portion 974 which extends parallel to thebottom surface of the pump base 902 (See FIG. 73). The interior recessedsurfaces of the nipple portion 972 include standoffs 976 which are snapreceived onto the outside surface of the inlet port 920 maintaining aflow channel therebetween (See FIGS. 73-74). The upper surface of theflange portion 974 includes a plurality of upwardly extending detents978 which maintain spacing between the flange portion 974 and the bottomsurface of the pump base 902 and maintain a flow channel to the inletport 920. FIG. 74 best illustrates the flow path of product from thecontainer 914 around the baffle 970 and into the inlet port 920. Theadded baffle 970 covers the inlet port 920 and prevents product fromdirectly entering the inlet port 920 and being pulled into theaccumulator 910 before the headspace air has been evacuated duringpriming strokes. The combination of the vents 960 and baffle 970 reducesthe variation in output volume and reduces the number of strokes toprime the pump 900 making for a better customer experience.

Turing to FIGS. 75-80, a variation of the dispensing pump 900 isindicated at 900A. The dispensing pump 900A may in all aspects beidentical to the embodiment 900 with the same components except thebaffle 970A which is best seen in FIGS. 77-80. The baffle 970A includesa central nipple portion 972 with standoffs 976 and a modified flangeportion 974A. The flange portion 974A is slightly shorter in radiallength and includes a plurality of circumferentially spaced fingers 980which extend outwardly and upwardly from the outer peripheral edge ofthe flange portion 974A. The fingers 980 cooperate with the previouslydescribed detents 978 to maintain a flow channel between the baffle 970Aand the pump base 902. FIG. 80 best illustrates the flow path of productfrom the container 914 around the baffle 970A and into the inlet port920.

Turing to FIGS. 81-86, another variation of the dispensing pump 900 isindicated at 900B. Again, the dispensing pump may in all aspects beidentical to the embodiment 900 with the same components except thebaffle 970B which is best seen in FIGS. 83-86. The baffle 970B includesa central nipple portion 972 with standoffs 976 and another modifiedflange portion 974B. The flange portion 974B is again shorter in radiallength and includes an upwardly turned rim 982 extending upwardly fromthe outer peripheral edge of the flange portion 974B. The rim 982 turnsupwardly into an annular space in the bottom wall of the pump base 902and maintains a flow channel between the baffle 970B and the pump base902. The flange 974B also includes the previously noted detents 978.FIG. 86 best illustrates the flow path of product from the container 914around the baffle 970B and into the inlet port 920.

Turning now to FIGS. 87-92, still another exemplary embodiment of adispensing pump is illustrated and generally indicated at 1000. Thedispensing pump 1000 is substantially similar to the above-describedembodiment 800 in structure and function with two exceptions which alsoresolve the same issues described with excess air in the headspace andinconsistent pumping volumes. The pump 1000 may also include the sameventing structures 1060 on the outer peripheral surfaces of the pumpbase 1002. However, in the place of the baffle, the inlet port 1020 ismodified so that it is formed flush or co-planar with the bottom surfaceof the pump base 1001 and the ball valve is replaced with a disc valve1090.

The major working components of dispensing pump 1000 are the same withthe exception of the shape of the inlet port 1020 and the disk valve1090. The dispensing pump 1000 comprises a pump base 1002, a dispensinghead 1004 and a polymer compression spring assembly 1006. The pump base1002 is snap received within the neck 1012 of a container or jar 1014.The pump base 1002 may be provided with the same peripheral vents 1060or relief areas as described above.

A cup-shaped cap 1016 is snap received over the dispensing head 1004.The exemplary embodiment 1000 also further includes a piston follower1018. As similarly descried above, the accumulator cup 1010 has an inletport 1020 formed in the bottom wall thereof. The disk valve 1022 islocated within the inlet port 1020 and has a central body portion 1092which extends through the inlet port and a peripheral flange portion1094 which is seated within the accumulator cup 1010.

Piston stem 1034 and piston seal 1046 are assembled with the dispensinghead 1004 as also described above.

The compression spring assembly 1006 is the same as describedhereinabove comprising a cylindrical slotted tubular spring element 1048and first and second loading cones integrally formed with the pump base1002 and the piston stem 1034.

As best seen in FIG. 92, the shortened inlet port 1020 reduces headspacebetween the bottom surface of the pump base and the product and can nolonger dip into product before air in the headspace is evacuated.

It can therefore be seen that the exemplary embodiments provide uniqueand novel dispensing pump assemblies in which all the discretecomponents may be molded from a single plastic material or relatedrecyclable plastics to facilitate single stream plastic recycling.Further, the all plastic compression spring assemblies can beadvantageously used in all plastic dispensing pumps which can then alsobe easily recycled.

While there is shown and described herein certain specific structuresembodying various embodiments of the invention, it will be manifest tothose skilled in the art that various modifications and rearrangementsof the parts may be made without departing from the spirit and scope ofthe underlying inventive concept and that the same is not limited to theparticular forms herein shown and described except insofar as indicatedby the scope of the appended claims

What is claimed is:
 1. A dispensing pump comprising: a pump base; anaccumulator within the pump base; an inlet port within the accumulator;a valve within the inlet port; a baffle disposed over the inlet port; adispensing head having an outlet nozzle and an inlet stem; a piston stemhaving an interior flow passage, an upper end received with the inletstem of the dispensing head and an opposing lower end with an inletopening extending into said accumulator; a piston seal at said lower endof said piston stem, said piston seal engaging said accumulator; and acompression spring captured between the piston stem and the pump base,said compression spring comprising: a slotted tubular spring elementformed from a tensile polymer material; a first loading cone disposedconcentrically around the accumulator at a first end of said slottedtubular spring element; and a second loading cone disposedconcentrically around the piston stem at said second end of said slottedtubular spring element, said second loading cone being axiallycompressible with said piston stem and said dispensing head toward thefirst loading cone, whereby said slotted tubular spring element radiallyexpands to create an opposing extension spring force.
 2. The dispensingpump of claim 1 wherein said first loading cone is annular and isintegrally molded with the pump base and wherein said second loadingcone is integrally molded with the piston stem.
 3. A dispensing pumpcomprising: a pump base; an accumulator within the pump base; an inletport within the accumulator wherein an external surface of said inletport is coplanar with an external bottom surface of said pump base; avalve within the inlet port; a dispensing head having an outlet nozzleand an inlet stem; a piston stem having an interior flow passage, anupper end received with the inlet stem of the dispensing head and anopposing lower end with an inlet opening extending into saidaccumulator; a piston seal at said lower end of said piston stem, saidpiston seal engaging said accumulator; and a compression spring capturedbetween the piston stem and the pump base, said compression springcomprising: a slotted tubular spring element formed from a tensilepolymer material; a first loading cone disposed concentrically aroundthe accumulator at a first end of said slotted tubular spring element;and a second loading cone disposed concentrically around the piston stemat said second end of said slotted tubular spring element, said secondloading cone being axially compressible with said piston stem and saiddispensing head toward the first loading cone, whereby said slottedtubular spring element radially expands to create an opposing extensionspring force.
 4. The dispensing pump of claim 3 wherein said firstloading cone is annular and is integrally molded with the pump base andwherein said second loading cone is integrally molded with the pistonstem.